New Down syndrome growth charts released

Researchers have developed new growth charts for children with Down syndrome (DS)
to replace charts dating back to 1988.

Since the charts were first released, weight gain for children under 3 years has improved,
and height for males ages 2-18 years has increased, according to a new report.

The Academy has not taken an official stance on the charts. However, Marilyn J. Bull,
M.D., FAAP, author of the Academy’s 2011 clinical report on Down syndrome, called
them “long-needed” and said she is “confident in their quality.”

“Clinicians will find the charts extremely useful for monitoring trends in weight
and height,” said Dr. Bull, a member of the AAP Council on Children With Disabilities.
“Any child found longitudinally who crosses percentiles warrants careful assessment.”

Roughly one in 700 live births is a child with Down syndrome, and those children tend
to grow more slowly than other children, according to the report.

Growth charts specifically for children with Down syndrome were published in Pediatrics in 1988. However, in the 2011 AAP clinical report Health Supervision for Children With Down Syndrome (bit.ly/1KFLXTG), the Academy recommended using standard charts from the Centers for Disease Control
and Prevention’s (CDC’s) National Center for Health Statistics or the World Health
Organization because the 1988 charts were outdated.

Researchers from The Children’s Hospital of Philadelphia (CHOP) and the CDC partnered
to develop the Down Syndrome Growing Up Study (DSGS), which looks at recent growth
trends and compares them with the 1988 U.S. charts as well as 2002 charts from the
United Kingdom.

The study enrolled 637 children up to age 20 years with Down syndrome. Compared to
the 1988 growth curves, the DSGS showed:

improvement in weight gain for birth to 3 years,

similar lengths for females from birth to 3 years,

slightly greater lengths for males from birth to 3 years,

roughly the same weight curves for many children ages 2-18 years,

increases in height for males at most ages from 2-18 years and

some increases in height for females in early to mid-puberty but similar final heights.

In many areas, the DSGS curves were similar to the U.K. curves from 2002.

The CHOP/CDC report presents updated growth charts for weight, length and height,
although it does not represent an official CDC recommendation. It also includes weight-for-length
charts for children from birth to 3 years, body mass index (BMI) charts for those
2-20 years and head circumference charts for both age groups.

“These growth charts are designed to be used as screening tools to assess growth and
nutritional status, and provide indications of how the growth of an individual child
compares with peers of the same age and sex with DS,” according to the report.

Dr. Bull said they also can be reassuring for parents who question whether their child’s
growth is on track.

The authors acknowledge several limitations in their research. The sample of children
came from those attending clinics and community events and was not random. It may
not be representative of the population at large since it drew mostly from the greater
Philadelphia area and does not contain data from families who declined to participate
in the study.

The growth curves also represent current trends but not necessarily optimal growth.
Dr. Bull said children with Down syndrome tend to have low metabolic rates, and some
have poor diets.

“Until optimal BMI guidelines for individuals with Down syndrome are established,
clinicians should use the BMI guidelines of the CDC charts,” she said.